Tomi, a woman married to an older man, masturbates to a penis etched on a wall inside a subway toilet. She begins searching for the guy who owns the alias that is written next to the etched penis. She meets a pervert on the subway and lets him molest her. Tamako, a female college student who witnesses the molestation, reports the man and someone beside him named Asami, who she thinks is also an accomplice, to the authority, but the two men aren't arrested because Tomi denies that she was molested. This is how the two women meet, and Tomi tells Tamako about the etched penis in the subway toilet and her search for the guy whose name was written beside it. Tamako follows Tomi to her lover Shinji's place, where Tomi finds him with another woman, fights with her and kicks her out and makes love to him. Tamako also witnesses Tomi fucking a business owner inside his restaurant. Later, after Tomi rejects Shinji on the street, Tamako takes him to the subway toilet where the etched penis is and makes love to him there. Tomi, meanwhile, follows Asami, who she thinks is the owner of the alias beside the etched penis. She has sex with him in a hotel room. A few days later, Tomi gets on the bus and witnesses a guy bashing his wife's head with a concrete block for cheating on him. She's not sure why, but she gets aroused by the situation. The guy hijacks her bus with only her remaining in it and drives it in the middle of nowhere, where the two make love and find in each other eternal pleasure.